What size breaker do I need to supply a 63A consumer unit

We have no electricians here familiar with UK standards, appears that a 100 amp main is typical for a 63 AMp Consumer Unit, see:

Consumer Unit 12 Way 63 Amp Dual RCD & 100 Amp Main Switch - Consumer Unit 12 Way 63 Amp Dual RCD & 100 Amp Main Switch - Consumer Unit Dual RCD 17th Edition (2x RCDs & 1x Main Switch) - Consumer Unit - Expert Electrical (http://www.expert-electrical.co.uk/Consumer-Unit/Consumer-Unit-Dual-RCD-17th-Edition-2x-RCDs-1x-Main-Switch-/Consumer-Unit-12-Way-63-Amp-Dual-RCD-100-Amp-Main-Switch/prod_418.html)